code: def testInvalidFilename(self):
      self.assertComputeFails(
          MonoWriter(filename=""), ([0.1, 0.2, 0.3])
      )
  
file_path: essentia/test/src/unittests/io/test_monowriter.py
imports: from essentia_test import *
  import sys
  from numpy import pi, sin
  import os
label_desc: Use image node_id 4 for calling the TestMonoWriter obj's underlying member method code with example usage: obj.testInvalidFilename() without return types